When Lady Alexandra Calthorpe arrives at the Colorado ranch managed by her uncle, she has little idea of how the experience will alter the future her father has in mind for her. Headstrong and willful, Alex learns to lasso more than the corral fence post as she tries to emulate the lives of the cowpunchers around her and cross the divide from the strictures of Victorian English society to the freedom of the American west. Having overcome a disastrous marriage in England, and with a burgeoning art career in New York, she tries to reconcile her desire for independence with her love for top hand Jesse Makepeace. But when the brutal winter of 1886 blows in killing most of the ranch herd, Alex sees the life she had hoped for on the open range changed forever.